Valves
 

Working on a car that had the motor "rebuilt" many years ago and has virtually no run time in it Changed all fluids and removed and cleaned the oil pan and tray. Car starts and runs great. Valves are noisy and I checked to make sure they are not sticking. Major problem seems to be excessive lash on the exhaust valves. I have 4 new valves to install. What is the best way to shorten the new valves to the proper length/lash. Do I need to make a "jig" to hold the valve so I can file the necessary amount off the end to get the proper lash? Is there a better way? The engine is not out of the car.

Re: Valves
 

Back in the day a special grinder was used. The valve was held perpendicular to the grinding wheel face (side) and moved into contact to remove the required material. The trick is to get the end square and perpendicular to the stem. Depending on your fabrication skills, you could make a holder for the valve that is mounted on a hinge to move it into contact with your grinder. Just be careful not to grind too much off. I think the old machines had a way to dial in the amount to be taken off the valve.

Of course, most people today use modern valves and adjustable lifters in their Model A's. But the old style will work, just more effort required.

Re: Valves
 

If there is excessive lash on the valves, you would need to have longer valves, not shorter. I would install a set of modern valves with adjustable tappets and forget it.

Re: Valves
 

Synchro909 has it right.

Re: Valves
 

Yes, I understand that. However I am hoping that the new valves will be long enough to allow for grinding to the proper length to provide the correct lash. I will know better once I get the car out of winter storage this month and test fit the new valves. If this doesn't work out, I realize that the only proper solution will be adjustable lifters. Just hoping to avoid taking the motor out and eating into my summer driving season. My real question was simply how to best shorten the new valves if they are long enough to accommodate this.

Re: Valves
 

If you were my neighbor, we could clean up the valve seat with a valve seating tool. Install the new valve and guide. Check the valve clearance and if you need the valve to set a LITTLE deeper take a few thousandths more. Valves that are too long can have their bases faced in a lathe.
Dan

Re: Valves
 

Most older valve grinding machines have a fixture on one end to resurface the valve tips but a lot depends on how much needs to be removed. Cutting or grinding the valves or seats in the valve pockets will affect the clearances as well. If a person has the old mushroom tipped valves then the clearance has to be set before the valves and guides are reinstalled. This can be tricky. If a person has the modern one piece guides and the straight stem valves then that makes it a more straight forward procedure.

Re: Valves
 

Thanks everyone. I guess I'll just wait and see how close the new valves come to the proper clearance. If they are quite close to specs, I will either try to grind a little off the seat by using a manual valve grinding tool or grind a little of the mushroom tip of the stem, whichever is needed

Re: Valves
 

New valves typically are a little bit longer so you shouldn't have any problem with clearance I just need to grind a little bit

Re: Valves
 

It is possible to change out the lifters with the engine in the car. Remove the radiator and pan and the covers over the cam gear. Remove the valve springs, guides, and valves. Remove the cam gear. Pull up the lifters and hold them up with clothes pins. Pull out the cam. Remove the clothes pins and the lifters will drop out the bottom of the engine. Push the new lifters up into position with a little grease to hold them up and then use the clothes pins. Put the cam back in and re install all the other stuff including modern valves, new guides, keepers, and springs. Then adjust the valves.

Use the two wrench lifters that are far easier to adjust. Use the "rule of 9" to adjust the valves where the tappet clearance is measure at valve 1 while 8 is up and then adjusted while it is up, etc. It sounds like you have the mechanical ability to do this job.

Re: Valves
 

He said he was replacing the short valves.

Re: Valves
 

When installing new valves they should be faced and the seats clean cut/ground. I can't recommend just plooping in new valves.

Why not check the lash on what you have and let us know what they are.

Doing the same to your old valves[ facing and cutting seats] decreases the lash. Any old auto shop with a dusty old valve grinding machine sitting in the corner can do the job or probably would be glad to sell it to you. On the right end of it is a holder and micrometer for cutting the stem. Once the lash is know [after cutting the face and seat] you have a good idea how much needs to be taken off the stem, if any.

Re: Valves
 

I checked the lash on the valves before I stored the car for the winter. Intakes were all within spec (.010-.012) but the exhausts were all .025 or slightly more.

Re: Valves
 

.025" is getting wide even with a 'B' cam. I would think that can be reduced without new valves.

Re: Valves
 

Maybe so. I just thought I'd pick up a few valves while I am here in the US just in case I need them. Going back home (Canada) on the weekend

Re: Valves
 

Extra parts are a good thing.

Re: Valves
 

Usually the clearance decreases as the valve seats wear since they wear down and not up. With that much extra clearance, I'd be wondering if they were set up too loose at last overhaul. Exhaust are generally set with a bit more clearance than intakes for that reason but .010" more clearance is not natural unless the cam or followers are wearing a lot more than usual.

Re: Valves
 

Kinda my thoughts too, but, wear on just the exhaust side ?

I was thinking maybe it has a 'B' cam and they were set at .022" [or more] at the rebuild.

Re: Valves
 

This engine was done in stages in the 1960's. New rod and main bearings done by an old time machinist, engine bored and new pistons and rings (.125 o.s.) installed a couple of years later at an engine rebuilder's. I did final assembly myself but at this point can't remember if or how I set the valves. I know I replaced a few broken valve guides, probably with used ones that I had on hand and I think I lapped the valves in by hand. No indication that it has a B cam. It was just an old worn out motor when I pulled it out of a 29 Tudor back in the day. I'll see what happens when I go at it later in the month.

Re: Valves
 

Its kind of a crap shoot then. You might be able to somewhat measure the lift and maybe see what you have.

I'm sure at .025" you can hear them rattle a bit. A little rattle doesn't hurt anything or bother me.